# SPDX-License-Identifier: GPL-2.0 # Backward compatibility asflags-y += $(EXTRA_AFLAGS) ccflags-y += $(EXTRA_CFLAGS) cppflags-y += $(EXTRA_CPPFLAGS) ldflags-y += $(EXTRA_LDFLAGS) # flags that take effect in current and sub directories KBUILD_AFLAGS += $(subdir-asflags-y) KBUILD_CFLAGS += $(subdir-ccflags-y) # Figure out what we need to build from the various variables # =========================================================================== # When an object is listed to be built compiled-in and modular, # only build the compiled-in version obj-m := $(filter-out $(obj-y),$(obj-m)) # Libraries are always collected in one lib file. # Filter out objects already built-in lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m))) # Determine modorder. # Unfortunately, we don't have information about ordering between -y # and -m subdirs. Just put -y's first. modorder := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko)) # Handle objects in subdirs # --------------------------------------------------------------------------- # o if we encounter foo/ in $(obj-y), replace it by foo/built-in.a # and add the directory to the list of dirs to descend into: $(subdir-y) # o if we encounter foo/ in $(obj-m), remove it from $(obj-m) # and add the directory to the list of dirs to descend into: $(subdir-m) __subdir-y := $(patsubst %/,%,$(filter %/, $(obj-y))) subdir-y += $(__subdir-y) __subdir-m := $(patsubst %/,%,$(filter %/, $(obj-m))) subdir-m += $(__subdir-m) obj-y := $(patsubst %/, %/built-in.a, $(obj-y)) obj-m := $(filter-out %/, $(obj-m)) # Subdirectories we need to descend into subdir-ym := $(sort $(subdir-y) $(subdir-m)) # if $(foo-objs), $(foo-y), or $(foo-m) exists, foo.o is a composite object multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m)))) multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))), $(m)))) multi-used := $(multi-used-y) $(multi-used-m) single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m))) # $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to # tell kbuild to descend subdir-obj-y := $(filter %/built-in.a, $(obj-y)) # Replace multi-part objects by their individual parts, # including built-in.a from subdirectories real-obj-y := $(foreach m, $(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) real-obj-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)),$(m))) # DTB # If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built extra-y += $(dtb-y) extra-$(CONFIG_OF_ALL_DTBS) += $(dtb-) # Add subdir path extra-y := $(addprefix $(obj)/,$(extra-y)) always := $(addprefix $(obj)/,$(always)) targets := $(addprefix $(obj)/,$(targets)) modorder := $(addprefix $(obj)/,$(modorder)) obj-m := $(addprefix $(obj)/,$(obj-m)) lib-y := $(addprefix $(obj)/,$(lib-y)) subdir-obj-y := $(addprefix $(obj)/,$(subdir-obj-y)) real-obj-y := $(addprefix $(obj)/,$(real-obj-y)) real-obj-m := $(addprefix $(obj)/,$(real-obj-m)) single-used-m := $(addprefix $(obj)/,$(single-used-m)) multi-used-m := $(addprefix $(obj)/,$(multi-used-m)) subdir-ym := $(addprefix $(obj)/,$(subdir-ym)) # Finds the multi-part object the current object will be linked into. # If the object belongs to two or more multi-part objects, all of them are # concatenated with a colon separator. modname-multi = $(subst $(space),:,$(sort $(foreach m,$(multi-used),\ $(if $(filter $*.o, $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$(m:.o=))))) modname = $(if $(modname-multi),$(modname-multi),$(basetarget)) # These flags are needed for modversions and compiling, so we define them here # $(modname_flags) defines KBUILD_MODNAME as the name of the module it will # end up in (or would, if it gets compiled in) name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote) basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \ $(ccflags-y) $(CFLAGS_$(basetarget).o) _c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags)) orig_a_flags = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) \ $(asflags-y) $(AFLAGS_$(basetarget).o) _a_flags = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags)) _cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F)) # # Enable gcov profiling flags for a file, directory or for all files depending # on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL # (in this order) # ifeq ($(CONFIG_GCOV_KERNEL),y) _c_flags += $(if $(patsubst n%,, \ $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \ $(CFLAGS_GCOV)) endif # # Enable address sanitizer flags for kernel except some files or directories # we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE) # ifeq ($(CONFIG_KASAN),y) _c_flags += $(if $(patsubst n%,, \ $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \ $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE)) endif ifeq ($(CONFIG_UBSAN),y) _c_flags += $(if $(patsubst n%,, \ $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \ $(CFLAGS_UBSAN)) endif ifeq ($(CONFIG_KCOV),y) _c_flags += $(if $(patsubst n%,, \ $(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \ $(CFLAGS_KCOV)) endif # If building the kernel in a separate objtree expand all occurrences # of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/'). ifeq ($(KBUILD_SRC),) __c_flags = $(_c_flags) __a_flags = $(_a_flags) __cpp_flags = $(_cpp_flags) else # -I$(obj) locates generated .h files # $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files # and locates generated .h files # FIXME: Replace both with specific CFLAGS* statements in the makefiles __c_flags = $(if $(obj),$(call addtree,-I$(src)) -I$(obj)) \ $(call flags,_c_flags) __a_flags = $(call flags,_a_flags) __cpp_flags = $(call flags,_cpp_flags) endif c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ -include $(srctree)/include/linux/compiler_types.h \ $(__c_flags) $(modkern_cflags) \ $(basename_flags) $(modname_flags) a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ $(__a_flags) $(modkern_aflags) cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ $(__cpp_flags) ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) DTC_INCLUDE := $(srctree)/scripts/dtc/include-prefixes dtc_cpp_flags = -Wp,-MD,$(depfile).pre.tmp -nostdinc \ $(addprefix -I,$(DTC_INCLUDE)) \ -undef -D__DTS__ # Useful for describing the dependency of composite objects # Usage: # $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add) define multi_depend $(foreach m, $(notdir $1), \ $(eval $(obj)/$m: \ $(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s))))))) endef # LEX # --------------------------------------------------------------------------- quiet_cmd_flex = LEX $@ cmd_flex = $(LEX) -o$@ -L $< $(obj)/%.lex.c: $(src)/%.l FORCE $(call if_changed,flex) # YACC # --------------------------------------------------------------------------- quiet_cmd_bison = YACC $@ cmd_bison = $(YACC) -o$@ -t -l $< $(obj)/%.tab.c: $(src)/%.y FORCE $(call if_changed,bison) quiet_cmd_bison_h = YACC $@ cmd_bison_h = $(YACC) -o/dev/null --defines=$@ -t -l $< $(obj)/%.tab.h: $(src)/%.y FORCE $(call if_changed,bison_h) # Shipped files # =========================================================================== quiet_cmd_shipped = SHIPPED $@ cmd_shipped = cat $< > $@ $(obj)/%: $(src)/%_shipped $(call cmd,shipped) # Commands useful for building a boot image # =========================================================================== # # Use as following: # # target: source(s) FORCE # $(if_changed,ld/objcopy/gzip) # # and add target to extra-y so that we know we have to # read in the saved command line # Linking # --------------------------------------------------------------------------- quiet_cmd_ld = LD $@ cmd_ld = $(LD) $(ld_flags) $(filter-out FORCE,$^) -o $@ # Objcopy # --------------------------------------------------------------------------- quiet_cmd_objcopy = OBJCOPY $@ cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ # Gzip # --------------------------------------------------------------------------- quiet_cmd_gzip = GZIP $@ cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \ (rm -f $@ ; false) # DTC # --------------------------------------------------------------------------- DTC ?= $(objtree)/scripts/dtc/dtc # Disable noisy checks by default ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) DTC_FLAGS += -Wno-unit_address_vs_reg \ -Wno-unit_address_format \ -Wno-avoid_unnecessary_addr_size \ -Wno-alias_paths \ -Wno-graph_child_address \ -Wno-graph_port \ -Wno-unique_unit_address \ -Wno-pci_device_reg endif ifneq ($(findstring 2,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) DTC_FLAGS += -Wnode_name_chars_strict \ -Wproperty_name_chars_strict endif DTC_FLAGS += $(DTC_FLAGS_$(basetarget)) # Generate an assembly file to wrap the output of the device tree compiler quiet_cmd_dt_S_dtb= DTB $@ cmd_dt_S_dtb= \ ( \ echo '\#include <asm-generic/vmlinux.lds.h>'; \ echo '.section .dtb.init.rodata,"a"'; \ echo '.balign STRUCT_ALIGNMENT'; \ echo '.global __dtb_$(subst -,_,$(*F))_begin'; \ echo '__dtb_$(subst -,_,$(*F))_begin:'; \ echo '.incbin "$<" '; \ echo '__dtb_$(subst -,_,$(*F))_end:'; \ echo '.global __dtb_$(subst -,_,$(*F))_end'; \ echo '.balign STRUCT_ALIGNMENT'; \ ) > $@ $(obj)/%.dtb.S: $(obj)/%.dtb FORCE $(call if_changed,dt_S_dtb) quiet_cmd_dtc = DTC $@ cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \ $(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \ $(DTC) -O dtb -o $@ -b 0 \ $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \ -d $(depfile).dtc.tmp $(dtc-tmp) ; \ cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) $(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE $(call if_changed_dep,dtc) dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp) # Bzip2 # --------------------------------------------------------------------------- # Bzip2 and LZMA do not include size in file... so we have to fake that; # append the size as a 32-bit littleendian number as gzip does. size_append = printf $(shell \ dec_size=0; \ for F in $1; do \ fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F); \ dec_size=$$(expr $$dec_size + $$fsize); \ done; \ printf "%08x\n" $$dec_size | \ sed 's/\(..\)/\1 /g' | { \ read ch0 ch1 ch2 ch3; \ for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \ printf '%s%03o' '\\' $$((0x$$ch)); \ done; \ } \ ) quiet_cmd_bzip2 = BZIP2 $@ cmd_bzip2 = (cat $(filter-out FORCE,$^) | \ bzip2 -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ (rm -f $@ ; false) # Lzma # --------------------------------------------------------------------------- quiet_cmd_lzma = LZMA $@ cmd_lzma = (cat $(filter-out FORCE,$^) | \ lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ (rm -f $@ ; false) quiet_cmd_lzo = LZO $@ cmd_lzo = (cat $(filter-out FORCE,$^) | \ lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ (rm -f $@ ; false) quiet_cmd_lz4 = LZ4 $@ cmd_lz4 = (cat $(filter-out FORCE,$^) | \ lz4c -l -c1 stdin stdout && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ (rm -f $@ ; false) # U-Boot mkimage # --------------------------------------------------------------------------- MKIMAGE := $(srctree)/scripts/mkuboot.sh # SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces # the number of overrides in arch makefiles UIMAGE_ARCH ?= $(SRCARCH) UIMAGE_COMPRESSION ?= $(if $(2),$(2),none) UIMAGE_OPTS-y ?= UIMAGE_TYPE ?= kernel UIMAGE_LOADADDR ?= arch_must_set_this UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR) UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)' UIMAGE_IN ?= $< UIMAGE_OUT ?= $@ quiet_cmd_uimage = UIMAGE $(UIMAGE_OUT) cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \ -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \ -T $(UIMAGE_TYPE) \ -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \ -n $(UIMAGE_NAME) -d $(UIMAGE_IN) $(UIMAGE_OUT) # XZ # --------------------------------------------------------------------------- # Use xzkern to compress the kernel image and xzmisc to compress other things. # # xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage # of the kernel decompressor. A BCJ filter is used if it is available for # the target architecture. xzkern also appends uncompressed size of the data # using size_append. The .xz format has the size information available at # the end of the file too, but it's in more complex format and it's good to # avoid changing the part of the boot code that reads the uncompressed size. # Note that the bytes added by size_append will make the xz tool think that # the file is corrupt. This is expected. # # xzmisc doesn't use size_append, so it can be used to create normal .xz # files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very # big dictionary would increase the memory usage too much in the multi-call # decompression mode. A BCJ filter isn't used either. quiet_cmd_xzkern = XZKERN $@ cmd_xzkern = (cat $(filter-out FORCE,$^) | \ sh $(srctree)/scripts/xz_wrap.sh && \ $(call size_append, $(filter-out FORCE,$^))) > $@ || \ (rm -f $@ ; false) quiet_cmd_xzmisc = XZMISC $@ cmd_xzmisc = (cat $(filter-out FORCE,$^) | \ xz --check=crc32 --lzma2=dict=1MiB) > $@ || \ (rm -f $@ ; false) # ASM offsets # --------------------------------------------------------------------------- # Default sed regexp - multiline due to syntax constraints # # Use [:space:] because LLVM's integrated assembler inserts <tab> around # the .ascii directive whereas GCC keeps the <space> as-is. define sed-offsets 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \ /^->/{s:->#\(.*\):/* \1 */:; \ s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ s:->::; p;}' endef # Use filechk to avoid rebuilds when a header changes, but the resulting file # does not define filechk_offsets (set -e; \ echo "#ifndef $2"; \ echo "#define $2"; \ echo "/*"; \ echo " * DO NOT MODIFY."; \ echo " *"; \ echo " * This file was generated by Kbuild"; \ echo " */"; \ echo ""; \ sed -ne $(sed-offsets) < $<; \ echo ""; \ echo "#endif" ) endef